1. Field of the Invention
The present invention relates generally to an item-supporting structure that can be used to support shelving or other elements for carrying or supporting any desired item. More particularly, the present invention relates to a support assembly for use in, for example, a knock-down shelving system, to adjustably support shelves.
2. Description of the Prior Art
Shelving systems having adjustable height shelves and so-called “knock-down” type shelving systems are known, and each has utility in many applications. For example, a knockdown shelving system with adjustable height shelves may be used in food service, industrial, commercial, hospital, and similar fields for storage of any desired items.
One type of known adjustable, knockdown shelving system is disclosed in U.S. Pat. No. 3,424,111 (Maslow) and U.S. Pat. No. 3,523,508 (Maslow), which are assigned to the assignee of the subject invention. The adjustable shelving system disclosed in these patents has achieved great commercial success under assignee's trademark SUPER ERECTA SHELF. This shelving system uses a plurality of cylindrical support posts provided with a series of equally spaced, annular grooves on its outer surface. A basic shelving system might include four support posts to support one or more formed-wire shelves, with each shelf having a frusto-conically-shaped collar at each corner for receiving a support post. A two-piece interlocking sleeve fits around the support post. The sleeve features a rib on its interior surface for engaging one of the grooves on the support post and has a frusto-conically-shaped outer surface, which is widest at the bottom, designed to complement the shape of the shelf collars. The support posts fitted with sleeves are received in the collars of each shelf to assemble the shelving system. When assembled, the weight of the shelf creates a radially-inwardly directed force between the collars and sleeves. This force brings the sleeves into a locking relation with the posts and creates a wedging force between the collars and sleeves.
While the SUPER ERECTA SHELF shelving system has proven very successful in providing an easy to assemble shelving system with a substantial load-bearing capacity, adjusting the shelves can sometimes require the use of a hammer or other tool to disengage the shelf collars from the sleeves. The weight of the shelf and any items supported thereon, especially over time, can build up the wedging force between the shelf collars and the sleeves to the point where a significant amount of force is needed to raise the shelf off of the sleeves.
A shelving system with easy to adjust shelves is provided in U.S. Pat. No. 5,415,302. This shelving system uses hanger brackets to permit easy installation and adjustment of the shelves without requiring the disassembly of the entire shelving system or the use of tools. This shelving system is known commercially under the trademark QWIKSLOT SHELF, and the patent is also assigned to the assignee of the subject invention. The QWIKSLOT SHELF shelving system uses support posts formed with a plurality of elongated slots at regular vertical intervals for receiving the hanger brackets. The slotted support post can also have annular grooves as discussed above in the SUPER ERECTA SHELF shelving system. A notch in each hanger bracket receives a truncated corner of a shelf.
The hanger brackets used in the QWIKSLOT SHELF shelving system allow for easy adjustment of the shelves. A potential drawback in some applications, however, is that shelves secured by means of the hanger brackets do not provide the heavy-duty load bearing capacity of other shelving systems, such as the SUPER ERECTA SHELF shelving system. In addition, the slots in the posts are not acceptable in some food service applications.
Still another type of successful shelving system, sold and marketed under the trademark METROMAX features a “knock-down” configuration that uses triangular support posts. Such a system is the subject of U.S. Pat. No. 4,811,670, U.S. Pat. No. 4,964,350, U.S. Pat. No. 5,271,337, and U.S. Pat. No. 5,279,231, which also are assigned to the assignee of the subject invention.
In U.S. Pat. No. 4,811,670, a corner assembly for securing each corner of a shelf to the triangular support post includes a wedge member, a corner bracket structurally associated with the shelf and a collar. The wedge member snap-fits on the support post, and the collar and corner bracket form a sleeve around the support post. The formed sleeve fits against the support post and wedge member and supports the shelf by a wedging force.
The shelving systems in U.S. Pat. No. 4,964,350, U.S. Pat. No. 5,271,337, and U.S. Pat. No. 5,279,231, feature modular shelves in combination with the triangular support posts. The modular shelves include a rectangular shelf frame formed from two end beams connected to two side beams. A center beam may be inserted between the end beams, parallel to the side beams, to increase the load-bearing capacity of the system. A plurality of plastic shelf mats are adapted to be snap-fit onto the shelf frame. The shelf frame is secured to the support post by corner assemblies comprised of a corner portion of the end beam, a wedge member and a separate collar. A sleeve formed by the corner portion and the collar is seated on the support post and wedge member and secured by a wedging action. Two lock cylinders lock the collar to the corner portion to secure the sleeve.
While the design of the modular shelf provides many advantages, adjusting the shelf can, on occasion, require use of a hammer or other tool to disengage the formed sleeve from the wedge member for the same reasons discussed above in connection with the SUPER ERECTA SHELF shelving system.
U.S. Pat. No. 6,017,009 and U.S. Pat. No. 6,113,042, each of which are incorporated herein by reference and are similarly assigned to the assignee of the subject invention, feature a support system for supporting a member on a support post. The support system of these two patents is sold and marketed under the trademark SUPER ADJUSTABLE SUPER ERECTA and the former patent also relates to a system sold under the mark METROMAX-Q. These patents feature a wedge assembly having a tapered face mountable on the support post, a collar, secured to the member to be supported, for example shelves, and a locking mechanism rotatably supported by the collar. The locking mechanism has a first position for press-fitting the wedge assembly against the support post, and a second position for allowing the collar to slide over the support post. The wedge member has beads on an inner surface for mating with grooves provided at least partially around the periphery of the support post. When the locking mechanism is in the first position, the beads of the wedge and the grooves mate to provide a secure fit.
FIG. 1 illustrates one corner of a shelving system utilizing the support assembly in accordance with the METROMAX-Q system. In this figure, a wire shelf frame 10 is positioned on an elongated support post 12 by a corner support assembly 14.
Generally speaking, the corner support assembly 14 is comprised of a collar 16 and a locking mechanism, or flipper, 18 rotatably mounted to the collar. In this view, the flipper is shown in its unlocked position. The corner support assembly is secured between an end outer rail 24 and a side outer rail 24′ which form part of the shelf frame 10. A tapered wedge member 20 is positioned on the post where the shelf frame is to be secured. With the flipper in the closed position, the wedge member is compressed against the support post 12, and the corner support assembly 14 surrounds the support post and wedge member like a sleeve and is seated thereon to support the shelf frame with a wedging force. In addition, as the shelf is loaded, the flipper and shelf will move downwardly relative to the wedge thereby to increase the force with which the wedge member engages the post.
As shown in FIG. 1, the wire shelf frame 10 is part of a modular shelf that is formed by securing the outer rails 24 and 24′ to the corner support assemblies 14 by conventional means such as welding. In a rectangular shelf configuration, for example, two end outer rails 24 and two side outer rails 24′ will be secured between four corner support assemblies to comprise the wire shelf frame. Each outer rail includes a top rail 26, a bottom rail 28 and a snake-like rail 30 secured between the top and bottom rails for stability. One or more transverse rails (unshown) can be secured between parallel outer rails for additional support and to increase the load-bearing capacity of the shelf.
FIG. 2 is an isolated view of the collar 16 as used in an exemplary disclosed embodiment of the METROMAX-Q system. The collar 16 includes a cylindrical shaft 34, preferably non-rotatable, secured between two lateral sides 36 for rotatably supporting the flipper 18. A rear section of the collar 16 joining, or connecting, the two lateral sides is contoured to fit the outward-facing shape of the post 12. The post has a generally triangular cross-section. The rear side is thus shaped to have a straight portion 35 angled from each lateral side and joined by a rounded apex 37.
FIG. 3 illustrates an exemplary locking mechanism, or flipper 18 as used in the METROMAX-Q system. The flipper, which is preferably integrally formed, has an upper end 41 and lower end 43. Further, the top end has a flat portion 47 and a rounded portion 49, with the rounded portion defining part of an open cylindrical cavity 40 for receiving and containing the shaft 34 of the collar 16. The lower end includes a flat manipulating portion 42 that can be grasped by the user. A rear face 44 of the flipper, which extends at an angle from the flat portion 47 and cannot be seen in FIG. 3, is shaped to complement the shape of the wedge member 20, which in this embodiment is substantially flat. The flipper is mounted on the collar to rotate about a longitudinal axis of the shaft. The preferred material for the flipper is a rigid molded plastic such as, for example, reinforced nylon.
FIG. 4A shows an example of a wedge member 20 used in the METROMAX-Q system. The wedge member 20 is designed to clip onto an interior face of the support post 12. The wedge member includes a front portion 45 flanked by two contoured lips 47 for clipping, or snap-fitting, the wedge member onto the support post. In addition, detent means such as internal beads, or ribs, 46 are provided on the internal surface of the wedge member and are spaced at intervals corresponding to the spacing of grooves on the support post.
The configuration of the internal beads is designed to mate with the configuration of the grooves in the support post. The internal beads provide vertical support when they are seated in the grooves of a support post. To further secure the wedge member on the support posts, additional vertical support is provided by a wedge action provided by the flipper in the locked position. The wedge member 20 may be clipped on to the support posts at any incremental height, and further may be translated up and down to any other incremental height.
In the example from the METROMAX-Q system illustrated in FIG. 4A, a cut-out 48 can be provided in the front portion 45 to view optional height increment numbers on the support post for vertically aligning the wedge member with wedge members on other support posts.
The outer surface of the front portion is substantially flat to correspond to the substantially flat rear face 44 of the flipper. Although not readily recognizable in FIG. 4A, the front portion is also slightly tapered from its upper end to its lower end, such that the lower end is wider and extends toward an interior of the shelving system.
With the tapered shape of the wedge member, an inwardly directed force is created by the weight of the shelf assembly to provide a wedging action between the corner support assembly and the wedge member, acting as in inclined plane.
As shown in FIG. 4B, the support post 12 has a generally right equilateral triangular cross-section, which can also be described as a triangular cross-section. A right-angled apex 50 and two flat exterior sides 52 face the exterior of the shelving system, and interior angled apexes 54 and an interior side 56 of the support post face the interior of the shelving assembly. The triangular geometry of the support post provides multi-directional stability, particularly in the directions of critical stress forces, i.e., in a direction parallel to the edges of the shelf.
The support post includes a plurality of horizontal grooves 58 that are preferably, but not necessarily, evenly spaced in the longitudinal direction of the post. The grooves receive the internal beads 46 of the sleeve.
Although unshown in the drawings, the top end of each support post 12 can be fitted with an end cap and the bottom end with a caster, a vertically-adjustable foot, an end cap, etc. As one example, the bottom end of the support post can be fitted with a stem receptacle for threadably receiving a leveling leg.
The METROMAX-Q system has been very successful and has provided users with an extremely easy to use yet sturdy adjustable mechanism for member support, in particular supports for heavy duty shelving requirements. This system can be improved so as to be even more convenient if a system can be devised in which the securing wedging action can be provided without using a separate wedge that may come loose from the other components of the corner support assembly. Thus, it would be advantageous if a support mechanism can be provided that has the advantages of the METROMAX-Q system mentioned above, while at the same time having the wedge, or structure that performs the wedging function of the wedge's inclined plane structure, inseparable or less readily separable from the other components of the corner support assembly.